When you buy a new phone from AT&T Wireless, your eSIM or SIM card is set up and activated. However, when you switch to AT&T and bring your existing phone, you must activate your new SIM card before using your plan. This guide walks you through activating an eSIM and SIM card through AT&T. You can follow this guide whether you have an AT&T prepaid or postpaid plan from the carrier or a prepaid card from another retailer. These prepaid cards are a great way to save money alongside a budget Android phone.
How to activate a SIM bought from an AT&T store
If you purchased your SIM kit from AT&T, activating your SIM is as simple as downloading your eSIM or inserting your physical SIM card. After this, you’ll receive a text confirming your plan is active. Postpaid and prepaid plans are automatically activated using this method.
Inserting a SIM card is straightforward, but downloading and activating an eSIM is trickier. This process varies between devices, even for phones from the same manufacturer. If you recently bought a postpaid AT&T eSIM, follow our comprehensive guide to download it to your phone.
If you don’t receive a confirmation text, follow the steps in the next section to manually activate your card.
How to activate an AT&T prepaid card
If you bought a SIM kit from a non-AT&T retailer and want to activate it with a new AT&T plan, the activation process is a little more complicated than inserting your SIM card. Follow these steps if the automatic activation does not work.
What you need to activate your prepaid AT&T SIM
You’ll need some information before activating your card. Install your SIM card or download your eSIM before you begin, as this makes finding the relevant information easier.
Your phone’s IMEI number
Your phone’s IMEI number is a unique identifier necessary for activating a SIM. You can find this number by dialing *#06# from your phone app. This method works for any Android phone or iPhone.
You can also find your phone’s IMEI number on its packaging and in the Settings app, under the About phone or About menu. You’ll see two IMEI numbers if your phone supports two SIM cards. These correspond to each SIM card slot in your phone, so write down the one in which you installed your AT&T SIM card.
If your phone supports eSIMs, they are also assigned a virtual “slot” and a corresponding IMEI number.
Your eSIM/SIM card number(ICCID number)
Your SIM card is assigned an ICCID number printed on the SIM card packaging. An eSIM’s ICCID number can be found in the same place as your phone’s IMEI number or on the prepaid activation card next to the QR code for eSIMs.
Your ICCID number may be labeled EID. In this case, you only need the last four digits to activate your SIM card.
After writing down these numbers, you’re ready to activate your AT&T SIM.
How to activate your AT&T prepaid card
After you install your SIM card or download your eSIM by scanning the QR code, AT&T sends a text message asking you to follow a link to activate your SIM. Alternatively, you can activate your SIM card online from any device or over the phone.
Activate online
Go to AT&T’s SIM activation page and enter your:
- ICCID or EID number
- IMEI number
- Service zip code (the zip code associated with your home address)
Next, follow the steps to choose and activate a plan. You’ll also enter an email address. These steps take you to a page confirming your payment. This page shows your prepaid phone number. Screenshot this or write it down until you have it memorized.
AT&T sends a text confirming your plan and asks you to set up an account to make future payments.
Activate your AT&T SIM over the phone
You can activate your AT&T SIM from the phone you’re installing it on. Call 877-426-0525 for automated instructions. Have your ICCID and IMEI numbers ready.
You cannot activate your AT&T SIM with an EID number over the phone.
How to check you’ve successfully activated your AT&T SIM
You should receive a confirmation text regardless of which method you use to activate your AT&T SIM. However, always make a test call to a friend, family member, or business to check that you successfully activated your SIM. If your phone call doesn’t go through, contact AT&T’s customer service.
Make sure you’re getting the best value data plan
It’s easy to default to one of the Big Three carriers (T-Mobile, Verizon, or AT&T) when choosing a phone plan. Still, it’s worth exploring MVNOs (mobile virtual network operators). These smaller companies piggyback on larger carriers’ networks, passing the savings from not maintaining the network to the customer. This means they are often better value than plans from big carriers, so explore the best MVNO unlimited data plans to see what you can save.
